13518219792
这有个友善的串口例程，参考下吧，用gcc编译可以在linux下用
创新互联建站于2013年成立，是专业互联网技术服务公司，拥有项目成都网站设计、网站建设网站策划，项目实施与项目整合能力。我们以让每一个梦想脱颖而出为使命，1280元乐安做网站,已为上家服务,为乐安各地企业和个人服务,联系电话:18980820575
# include stdio.h
# include stdlib.h
# include termio.h
# include unistd.h
# include fcntl.h
# include getopt.h
# include time.h
# include errno.h
# include string.h
int CommFd, TtyFd;
static void Error(const char *Msg)
{
fprintf (stderr, "%s\n", Msg);
fprintf (stderr, "strerror() is %s\n", strerror(errno));
exit(1);
}
static void Warning(const char *Msg)
{
fprintf (stderr, "Warning: %s\n", Msg);
}
static int SerialSpeed(const char *SpeedString)
{
int SpeedNumber = atoi(SpeedString);
# define TestSpeed(Speed) if (SpeedNumber == Speed) return B##Speed
TestSpeed(1200);
TestSpeed(2400);
TestSpeed(4800);
TestSpeed(9600);
TestSpeed(19200);
TestSpeed(38400);
TestSpeed(57600);
TestSpeed(115200);
TestSpeed(230400);
Error("Bad speed");
return -1;
}
static void PrintUsage(void)
{
fprintf(stderr, "comtest - interactive program of comm port\n");
fprintf(stderr, "press [ESC] 3 times to quit\n\n");
fprintf(stderr, "Usage: comtest [-d device] [-t tty] [-s speed] [-7] [-c] [-x] [-o] [-h]\n");
fprintf(stderr, " -7 7 bit\n");
fprintf(stderr, " -x hex mode\n");
fprintf(stderr, " -o output to stdout too\n");
fprintf(stderr, " -c stdout output use color\n");
fprintf(stderr, " -h print this help\n");
exit(-1);
}
static inline void WaitFdWriteable(int Fd)
{
fd_set WriteSetFD;
FD_ZERO(WriteSetFD);
FD_SET(Fd, WriteSetFD);
if (select(Fd + 1, NULL, WriteSetFD, NULL, NULL) 0) {
Error(strerror(errno));
}
}
int sendUart(char c)
{
WaitFdWriteable(CommFd);
return write(CommFd, c, 1);
}
char recUart()
{
char c='\0';
if (FD_ISSET(CommFd, ReadSetFD))
{
if(read(CommFd, c, 1) == 1) return c;
else printf("No data to receive.\n");
}
}
int main(int argc, char **argv)
{
struct termios TtyAttr;
struct termios BackupTtyAttr;
int DeviceSpeed = B115200;
int TtySpeed = B115200;
int ByteBits = CS8;
const char *DeviceName = "/dev/ttyS0";
const char *TtyName = "/dev/tty";
int OutputHex = 0;
int OutputToStdout = 0;
int UseColor = 0;
printf("Now we start.\n");
opterr = 0;
for (;;) {
int c = getopt(argc, argv, "d:s:t:7xoch");
if (c == -1)
break;
switch(c) {
case 'd':
DeviceName = optarg;
break;
case 't':
TtyName = optarg;
break;
case 's':
if (optarg[0] == 'd') {
DeviceSpeed = SerialSpeed(optarg + 1);
} else if (optarg[0] == 't') {
TtySpeed = SerialSpeed(optarg + 1);
} else
TtySpeed = DeviceSpeed = SerialSpeed(optarg);
break;
case 'o':
OutputToStdout = 1;
break;
case '7':
ByteBits = CS7;
break;
case 'x':
OutputHex = 1;
break;
case 'c':
UseColor = 1;
break;
case '?':
case 'h':
default:
PrintUsage();
}
}
if (optind != argc)
PrintUsage();
CommFd = open(DeviceName, O_RDWR, 0);
if (CommFd 0)
Error("Unable to open device");
if (fcntl(CommFd, F_SETFL, O_NONBLOCK) 0)
Error("Unable set to NONBLOCK mode");
memset(TtyAttr, 0, sizeof(struct termios));
TtyAttr.c_iflag = IGNPAR;
TtyAttr.c_cflag = DeviceSpeed | HUPCL | ByteBits | CREAD | CLOCAL;
TtyAttr.c_cc[VMIN] = 1;
if (tcsetattr(CommFd, TCSANOW, TtyAttr) 0)
Warning("Unable to set comm port");
TtyFd = open(TtyName, O_RDWR | O_NDELAY, 0);
if (TtyFd 0)
Error("Unable to open tty");
TtyAttr.c_cflag = TtySpeed | HUPCL | ByteBits | CREAD | CLOCAL;
if (tcgetattr(TtyFd, BackupTtyAttr) 0)
Error("Unable to get tty");
if (tcsetattr(TtyFd, TCSANOW, TtyAttr) 0)
Error("Unable to set tty");
for (;;) {
unsigned char Char = 0;
fd_set ReadSetFD;
void OutputStdChar(FILE *File) {
char Buffer[10];
int Len = sprintf(Buffer, OutputHex ? "%.2X " : "%c", Char);
fwrite(Buffer, 1, Len, File);
}
FD_ZERO(ReadSetFD);
FD_SET(CommFd, ReadSetFD);
FD_SET( TtyFd, ReadSetFD);
# define max(x,y) ( ((x) = (y)) ? (x) : (y) )
if (select(max(CommFd, TtyFd) + 1, ReadSetFD, NULL, NULL, NULL) 0) {
Error(strerror(errno));
}
# undef max
if (FD_ISSET(CommFd, ReadSetFD)) {
while (read(CommFd, Char, 1) == 1) {
WaitFdWriteable(TtyFd);
if (write(TtyFd, Char, 1) 0) {
Error(strerror(errno));
}
if (OutputToStdout) {
if (UseColor)
fwrite("\x1b[01;34m", 1, 8, stdout);
OutputStdChar(stdout);
if (UseColor)
fwrite("\x1b[00m", 1, 8, stdout);
fflush(stdout);
}
}
}
if (FD_ISSET(TtyFd, ReadSetFD)) {
while (read(TtyFd, Char, 1) == 1) {
static int EscKeyCount = 0;
WaitFdWriteable(CommFd);
if (write(CommFd, Char, 1) 0) {
Error(strerror(errno));
}
if (OutputToStdout) {
if (UseColor)
fwrite("\x1b[01;31m", 1, 8, stderr);
OutputStdChar(stderr);
if (UseColor)
fwrite("\x1b[00m", 1, 8, stderr);
fflush(stderr);
}
if (Char == '\x1b') {
EscKeyCount ++;
if (EscKeyCount = 3)
goto ExitLabel;
} else
EscKeyCount = 0;
}
}
}
ExitLabel:
if (tcsetattr(TtyFd, TCSANOW, BackupTtyAttr) 0)
Error("Unable to set tty");
return 0;
}
最好能将问题更准确的描述，看的费力！ 脚本和串口命令以及运行结果截个图上来看看
我估计是
参数没有正确传递进去。
串口读取从SHELL脚本传递进来的参数应该不是正确的。
你看一下运行串口程序的时候，是否开启了一个新的进程，并且重新初始化了所有变量。
将USB串口设备插入USB口后，会在/dev/目录下生成/dev/ttyUSB0文件（也可能为/dev/ttyUSB1,/dev/ttyUSB2...),
查看此文件
输出为:
c说明表明设备为字符设备文件（d表示目录文件，-表示普通文件，l表示链接文件，b表示块文件），
其中rw-rw----表示root用户作为文件所有者可以读和写，dialout用户组内的用户可以读和写，其他用户不允许读、写和执行（r表示可读，w表示可写，x表示可执行）
因此，需要将当前用户增加到dialout用户组中
